BMW + Mini - Good Valvetronic Article

Discussion in 'Other Manufacturers' started by Maxx, Mar 18, 2008.

  1. Maxx

    Maxx He who posts articles

  2. shifty35

    shifty35 Well-Known Member

    That's wierd, I thought all new Mini's had Valvetronic, including the S - I'll have to dig more. Valvetronic is a neat idea where the intake valves do the job of the throttle body, eliminating the pumping losses associated with it - however, there are still pumping losses associated with trying to completely fill a cylinder through a partially open valve. Same problem, different place.

    A crazy idea would be to apply the same type of technology to the crankshaft to vary the stroke. Haha, ok, that will never happen.

    The other thing mentioned is the need for overly stiff valve springs - this translates into more losses due to friction.

    I like the Honda method for dealing with pumping losses @ cruise found on the R18 - enable an Atkinson mode valve profile and open the throttle wide. True that it doesn't have the flexibility of Valvetronic, but it seems a bit simpler to implement (less moving parts, less things to break).
  3. Daox

    Daox Well-Known Member

    I agree. Theres still pumping losses, just in a different place. However, very interesting and good technology here. It allows increased torque throughout the entire rpm band, and much finer engine tuning capabilities.

    Saab was working on a way to dynamically change compression ratio on the fly. I forget exactly how they did it.

    Honda seems to be very good at simplifying things to work with fewer parts. For example the HCH-II's valve technology vs the Prius' elaborate drivetrain.

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